Application of guaiacol or guaiacol derivative in preparation of medicine for preventing or treating metabolic syndrome

Abstract

The invention relates to application of guaiacol or a derivative thereof in preparation of a medicine for preventing or treating metabolic syndrome, and belongs to the technical field of medicines. The guaiacol and the derivative thereof provided by the invention have the advantages that by regulating a fat metabolism pathway, the insulin resistance condition is obviously improved, the inflammatory response and oxidative stress injury are relieved, and the prevention and treatment on the metabolism-related fatty liver disease (MASLD), hyperlipidemia, hypercholesteremia, obesity and diabetes mellitus are realized through the synergistic effect of multiple dimensions.

Description

Technical Field

[0001] This invention relates to the technical field of medicine, specifically to the use of guaiacol or its derivatives in the preparation of drugs for the prevention or treatment of metabolic syndrome. Background Technology

[0002] With rising living standards and changing lifestyles, a series of health problems have emerged. Global analysis shows that by 2022, the total number of obese children, adolescents, and adults worldwide had exceeded 1 billion. Lancet . 2024;403(10431):1027-1050.). Obesity not only directly affects an individual's body shape and quality of life, but is also a major cause of various metabolic diseases.

[0003] Hyperlipidemia is a common symptom of obesity, and its incidence is increasing year by year. Numerous clinical studies have shown that the incidence of hyperlipidemia in obese people is as high as 40%. Excessively high lipid levels in the blood can lead to atherosclerosis, significantly increasing the risk of cardiovascular diseases such as coronary heart disease and cerebral infarction, seriously threatening people's lives and health.

[0004] Metabolic-associated fatty liver disease (MASLD) is closely related to obesity and hyperlipidemia. Due to increased intake of high-calorie, high-fat diets and decreased physical activity, the incidence of MASLD has exploded. Currently, its global prevalence has reached approximately 25%–30%, and it is showing a trend towards affecting younger people. Clinically, there are no specific drugs for MASLD; treatment mainly relies on lifestyle interventions, such as diet control and increased exercise. However, long-term adherence is difficult, and most patients do not respond well to treatment. Its pathogenesis is extremely complex, with insulin resistance, oxidative stress, and inflammatory responses interacting to continuously drive disease progression. If not effectively controlled, it may develop into serious liver diseases such as cirrhosis and liver cancer. On March 14, 2024, the U.S. Food and Drug Administration (FDA) approved Resmetirom for the treatment of adult patients with metabolic-associated fatty liver disease accompanied by liver fibrosis. Resmetirom became the first drug approved by the FDA for the treatment of metabolic-associated fatty liver disease (MASH), but data shows that only 30% of patients achieve clinical remission. Therefore, from a clinical perspective, there is still a lack of safe and effective drugs for the treatment of MASLD.

[0005] Diabetes is a common metabolic disease. With changing lifestyles and an accelerating aging population, the number of people with diabetes worldwide has increased dramatically in recent years, now exceeding 800 million. Long-term hyperglycemia can lead to a series of serious complications, such as diabetic nephropathy, diabetic retinopathy, and diabetic neuropathy. These complications severely reduce patients' quality of life and can even be life-threatening. Current treatments primarily focus on controlling blood sugar levels and delaying the onset of complications, but they cannot fundamentally stop the disease's progression. Therefore, finding more effective treatments is urgently needed.

[0006] Therefore, there is an urgent clinical need for a safe and effective drug that can simultaneously improve metabolic syndrome-related diseases.

[0007] Guaifenesin was approved for marketing in Japan in 1949. As a classic expectorant, although its mechanism of action is not fully understood, existing research suggests that it primarily works by thinning airway mucus and reducing its viscosity, while simultaneously relaxing the adhesion between the mucus and the airway walls, thus making sputum easier to cough up and effectively relieving symptoms of airway obstruction and congestion. It has been widely used clinically, including in pediatric patients. However, research on the prevention and treatment of metabolic-related fatty liver disease, hyperlipidemia, hypercholesterolemia, obesity, and diabetes using guaiacol glycerol is still lacking. Summary of the Invention

[0008] In view of the lack of research on the improvement of metabolic syndrome by guaiacol or its derivatives in existing public technologies, the present invention provides the application of guaiacol or its derivatives in the preparation of drugs for the prevention or treatment of metabolic syndrome, so as to solve the above-mentioned problem.

[0009] The technical solution of this invention is as follows: This invention provides the use of guaiacol or its derivatives in the preparation of drugs for the prevention or treatment of metabolic syndrome.

[0010] The guaiacol derivatives are guaiacol glycerol ether and guaiacolylglycerol-β-guaiacolylpropyl ether. The structure of guaiacol is shown in Formula I, the structure of guaiacol glycerol ether is shown in Formula II, and the structure of guaiacolylglycerol-β-guaiacolylpropyl ether is shown in Formula III. ; ; .

[0011] Furthermore, metabolic syndrome includes metabolic-related fatty liver disease, hyperlipidemia, hypercholesterolemia, obesity, and diabetes.

[0012] Furthermore, the metabolic-associated fatty liver disease includes metabolic-associated fatty liver (MASL) and metabolic-associated steatohepatitis (MASH).

[0013] Furthermore, the guaiacol or its derivative is the only active ingredient in the drug.

[0014] Furthermore, the effective concentration of the guaiacol or its derivative is ≥100 mg / kg. Here, "effective concentration" refers to the lowest concentration that achieves a therapeutic effect in mouse experiments.

[0015] Furthermore, the guaiacol or its derivatives also include pharmaceutically acceptable salts.

[0016] Furthermore, the drug for the prevention or treatment of metabolic syndrome includes pharmaceutically acceptable excipients.

[0017] Furthermore, the acceptable excipients are selected from one or more of the following: diluents, disintegrants, precipitation inhibitors, flow aids, binders, dispersants, suspending agents, isotonic agents, thickeners, emulsifiers, preservatives, stabilizers, hydrating agents, ion exchangers, flavoring agents, or antioxidants.

[0018] The beneficial effects of this invention are as follows: The guaiacol and its derivatives provided by this invention significantly improve insulin resistance by regulating lipid metabolism pathways, while reducing inflammatory response and oxidative stress damage. They work synergistically from multiple dimensions to achieve the prevention and treatment of metabolic-associated fatty liver disease (MASLD), hyperlipidemia, hypercholesterolemia, obesity and diabetes. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a graph showing the results of the cytotoxicity test of guaiacol or its derivatives on HepG2 cells. In the graph, A shows the effect of different concentrations of guaiacol on the activity of HepG2 cells; B shows the effect of different concentrations of guaiacol glycerol ether on the activity of HepG2 cells; and C shows the effect of different concentrations of guaiacol-glycerol-β-guaiacol propyl ether on the activity of HepG2 cells.

[0021] Figure 2 This is a graph showing the changes in triglyceride levels in HepG2 cells after intervention with guaiacol or its derivatives. A represents the normal control group; B represents the fatty acid model group (oleic acid-palmitic acid); C represents the guaiacol intervention group; D represents the guaiacol glycerol ether intervention group; and E represents the guaiacol-β-guaiacol propyl ether intervention group.

[0022] Figure 3This image shows lipid deposition in HepG2 cells after intervention with guaiacol or its derivatives, stained with Oil Red O. A represents the normal control group; B represents the fatty acid model group (oleic acid-palmitic acid); C represents the guaiacol intervention group; D represents the guaiacol glycerol ether intervention group; and E represents the guaiacol-glycerol-β-guaiacol propyl ether intervention group.

[0023] Figure 4 This study investigates the effects of guaiacol glycerol ether on the expression of lipid metabolism-related proteins. Figure A shows the effects of immunoblotting on the expression of ACC, FASN, SCD1, P-AMPK, and AMPK proteins; Figure B shows the grayscale analysis results of ACC, FASN, SCD1, P-AMPK, and AMPK protein expression, with HSP90 protein serving as a control.

[0024] Figure 5 This is a graph showing the experimental results of guaiacol glycerol ether improving insulin resistance and lowering blood glucose in obese mice. In the graph, A represents the fasting blood glucose level of mice in each experimental group; B represents the glucose tolerance test (GTT) curves of mice in each experimental group; C represents the area under the GTT curve of mice in each experimental group; D represents the insulin tolerance test (ITT) curves of mice in each experimental group; and E represents the area under the ITT curve of mice in each experimental group.

[0025] Figure 6 This is a diagram showing the experimental results of guaiacol glycerol ether in improving obesity in mice. A shows the changes in body weight of mice in each experimental group; B shows morphological photographs of mice in each experimental group; C shows the ratio of fat body weight to body weight of mice in each experimental group; D shows the ratio of defatted body weight to body weight of mice in each experimental group; and E shows the morphology of brown adipose tissue (BAT), epididymal white adipose tissue (eWAT), and inguinal white adipose tissue (iWAT) of mice in each experimental group.

[0026] Figure 7 This is a graph showing the experimental results of guaiacol glycerol ether improving metabolic-associated fatty liver disease (MASLD). In the graph, A represents the liver morphology of mice in each experimental group; B represents the liver weight of mice in each experimental group; C represents the liver index of mice in each experimental group; D represents the liver TG content of mice in each experimental group; E represents the liver TC content of mice in each experimental group; F represents the serum ALT of mice in each experimental group; G represents the serum AST of mice in each experimental group; and H represents the AST / ALT ratio of mice in each experimental group.

[0027] Figure 8 This is a diagram showing the effect of guaiacol glycerol ether on liver pathology in mice with metabolic-associated fatty liver disease (MASLD). In the diagram, A shows HE staining of the livers of mice in each experimental group; B shows Oil Red O staining of the livers of mice in each experimental group.

[0028] Figure 9The results of experiments showing that guaiacol glycerol ether improves metabolic-associated steatohepatitis (MASH) in mice. Figure 1 Where A represents the liver morphology of mice in each experimental group; B represents the body weight of mice in each experimental group; C represents the liver weight of mice in each experimental group; and D represents the liver index of mice in each experimental group.

[0029] Figure 10 The results of experiments showing that guaiacol glycerol ether improves metabolic-associated steatohepatitis (MASH) in mice. Figure 2 A represents serum ALP in mice of each experimental group; B represents serum ALT in mice of each experimental group; C represents serum AST in mice of each experimental group.

[0030] Figure 11 These are pathological images of liver injury and fibrosis in mice with guaiacol glycerol ether-mediated improvement of metabolic-associated steatohepatitis (MASH). In the images, A shows HE staining of the livers from each experimental group; B shows Masson staining of the livers from each experimental group. Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0032] Example 1 Guaiacin and its derivatives alleviate fatty acid-induced lipid deposition and triglyceride levels in HepG2 cells. 1. Materials and Methods: (1) Human HepG2 cells were used for in vitro experiments. The culture medium was DMEM low glucose medium containing NEEA (non-essential amino acids), 10% fetal bovine serum, 100 units / ml of penicillin and 0.1 mg / ml of streptomycin. The cells were cultured in an incubator at 37℃.

[0033] (2) Preparation of stock solutions: Guaiacol glycerol ether (CAS: 93-14-1), guaiacol (CAS: 90-05-1), and guaiacol-glycerol-β-guaiacol propyl ether (CAS: 7382-59-4) were all purchased from MCE China (website: https: / / www.medchemexpress.cn). The above three compounds were dissolved in DMSO to prepare a stock solution with a concentration of 40 mM. The DMSO solution of the above three compounds was then filtered through a 0.22 μm sterile filter membrane to obtain the stock solution for later use.

[0034] (3) Compound toxicity assay: HepG2 cells in the logarithmic growth phase were seeded into 96-well plates (5000 cells / well) and cultured overnight. Then, different final concentrations of guaifenesin, guaiacol, and propanediol were added and the cells were cultured for 24 hours. The final concentrations of the three compounds were 0 μM, 10 μM, 20 μM, 40 μM, 80 μM, 160 μM, and 320 μM, respectively, prepared by diluting the stock solutions to the predetermined concentrations. The toxicity of the compounds was then determined by adding CCK8 working solution according to the kit instructions.

[0035] (4) Cell lipid deposition assay: HepG2 cells in the logarithmic growth phase were seeded into 12-well plates containing cell spreaders. After overnight culture, OA-PA (oleic acid-palmitic acid: 250 μM - 125 μM, abbreviated as FFA) was added to the final concentration and cultured for another 4 hours. Then, guaifenesin, guaiacol, and guaifenesin-β-guaifenesin-propyl ether were added to the final concentration of 80 μM and cultured for another 24 hours. After cell treatment, the following steps were performed: After cell treatment, the cells were slowly washed 2-3 times with pre-cooled PBS buffer. The PBS buffer was discarded, 4% paraformaldehyde was added, and the cells were incubated on ice for 15 minutes. Then, the cells were slowly washed 3 times with PBS buffer for 3 minutes each time. The cell spreaders were removed, placed in a clean 6-well plate, and 60% isopropanol aqueous solution was added and incubated for 5 minutes. After aspirating the 60% isopropanol aqueous solution, add Oil Red staining solution and stain in the dark for 20 minutes. Aspirate the Oil Red staining solution, add a 60% isopropanol aqueous solution for differentiation for 3-5 seconds, discard the 60% isopropanol solution, and slowly wash three times with PBS buffer. Stain with hematoxylin for approximately 2 seconds (staining time should not be too long to avoid making the hematoxylin color darker than Oil Red), wash with PBS buffer, then differentiate with a 1% hydrochloric acid-alcohol solution for 1-3 seconds, followed by rinsing with water to restore blue color. Finally, mount with glycerol gelatin and observe under a microscope.

[0036] (5) Triglyceride (TG) assay in cells: HepG2 cells in the logarithmic growth phase were seeded in 6-well plates and cultured overnight. OA-PA (250 μM - 125 μM, FFA) was added to the plates, and the cells were cultured for another 4 hours. Guaifenesin, guaiacol, and propanediol (to a final concentration of 80 μM) were then added, and the cells were cultured for another 24 hours. The following procedures were performed: The triglyceride content in the cell samples was determined using a tissue cell triglyceride enzymatic assay kit manufactured by Beijing Pulilai Company. Cells were washed twice with pre-cooled PBS buffer, followed by the addition of lysis buffer (200 μL of the kit's cell lysis buffer per well in a 6-well plate) and incubated at room temperature for 10 minutes. Cells were scraped from the culture plate using a cell scraper, and all lysis buffer was transferred to a new 1.5 ml EP tube. Transfer an appropriate amount of lysis buffer from one EP tube to another EP tube and place it on ice. Determine the protein concentration of the sample using a BCA protein quantification kit. Heat the remaining lysis buffer in a 70°C metal bath for 10 minutes, then centrifuge at 2000 rpm for 5 minutes at room temperature. The supernatant can be used for TG determination, following the instructions in the manufacturer's manual.

[0037] (6) Determination of the expression of lipid metabolism-related proteins by guaiacol glycerol ether: HepG2 cells in the logarithmic growth phase were seeded in 6-well plates and cultured overnight. Guaiacol glycerol ether (100 μM) was added and the cells were cultured for another 24 hours. The cells were washed twice with pre-cooled PBS buffer, and then 200 μL of RIPA cell lysis buffer (Beyotime, P0013B) was added. The cells were placed on ice for 10 minutes. The cells were scraped off the culture plate with a cell scraper, and as much lysis buffer as possible was transferred to a new 1.5 ml EP tube. The tube was centrifuged at 12000 rpm for 10 minutes. The supernatant was collected and SDS-PAGE protein loading buffer (Beyotime, P0015) was added. The tube was heated at 100℃ for 10 minutes. Then, Western blotting was performed, followed by gel imaging and grayscale analysis.

[0038] 2. Test Results The cytotoxicity of guaiacol and its derivatives was evaluated in vitro. Results showed that concentrations of the compound up to 320 μM had no significant effect on the viability of HepG2 cells. Figure 1 As shown. An in vitro MASLD cell model was established by stimulating HepG2 cells with OA-PA. HepG2 cells were then treated with guaiacol and its derivatives for 24 hours. Intracellular TG levels were then detected and Oil Red O staining was performed. The results showed that guaiacol and its derivatives significantly reduced TG levels and lipid droplet accumulation in HepG2 cells. Figure 2 and Figure 3 As shown.

[0039] Western blot results showed that guaiacol glycerol significantly downregulated the expression of ACC, FASN, and SCD1 proteins, but had no significant effect on P-AMPK expression. Figure 4 As shown.

[0040] Example 2 Guaifenesin alleviates insulin resistance, obesity, and MASLD in mice induced by a high-fat diet. 1. Materials and Methods: Forty 7-week-old male C57BL / 6J mice were first acclimatized for one week, then randomly divided into four groups: a normal diet control group (CD), a high-fat diet group (HFD), a high-fat diet-guaifenesin low-dose group (Guaifenesin-L, or Gua-L), and a high-fat diet-guaifenesin high-dose group (Guaifenesin-H, or Gua-H). Mice in the normal diet control group were fed a normal diet, while mice in the other groups were fed a 60% high-fat diet (Research Diet, D12492). After 9 weeks of feeding, mice in the Gua-L group were administered 100 mg / kg guaifenesin daily by gavage, and mice in the Gua-H group were administered 300 mg / kg guaifenesin daily by gavage. Guaifenesin was dissolved in physiological saline, and mice in the other groups were simultaneously administered physiological saline by gavage. This drug intervention continued for 8 weeks.

[0041] Five weeks after drug intervention, a glucose tolerance test (GTT) was conducted: mice were fasted for 16 hours but allowed free access to water. The mice were weighed and their weight recorded. The required injection dose of 20% glucose was calculated based on 1 g glucose / kg body weight. Blood was collected from the tip of the mouse tail, the first drop of blood was wiped away, and blood glucose was measured at 0 minutes using a glucometer. After 10 minutes of adaptation, the mice were injected intraperitoneally with the calculated glucose dose. Blood glucose was measured at 30, 60, 90, and 120 minutes after intraperitoneal injection, and the area under the curve was analyzed using GraphPad Prism.

[0042] Six weeks after drug intervention, an insulin tolerance test (ITT) was conducted in mice: all mice were fasted for 4 hours in advance, and their fasting blood glucose levels (0 minutes) were measured and recorded. Then, insulin was injected at a ratio of 0.75 units / kg body weight, and the blood glucose levels of the mice were recorded at 15 minutes, 30 minutes, 60 minutes, 90 minutes and 120 minutes after insulin injection. The area under the curve was analyzed using GraphPad Prism.

[0043] Eight weeks after drug intervention, mice were fasted for 12 hours but allowed free access to water. The following morning, after weighing, the mice were placed in a restraint tube to restrict their movement. Fat mass and lean mass were analyzed and recorded using a Bruker Minispec LF90II system. The mice were then anesthetized with avertin via intraperitoneal injection. Blood was collected from the retro-orbital venous plexus, the mice were fixed, the abdominal cavity was opened, and the liver was quickly dissected and removed. The liver was rinsed with 4°C saline, the membrane was removed, and the wet weight was measured. Liver index was calculated. Two appropriately sized liver tissues were separated from the right lobe of the liver, 1 cm from the edge: one liver tissue was transversely sectioned, fixed with 4% paraformaldehyde, routinely dehydrated, embedded in paraffin, sectioned, and stained with hematoxylin and eosin (HE); the other liver tissue was frozen sectioned for Oil Red O staining; the remaining liver tissue was stored at -80°C. Simultaneously, inguinal fat (iWAT), epididymal white fat (eWAT), and brown fat (BAT, between the scapulae on the back) were rapidly freed and harvested. A portion was fixed with 4% paraformaldehyde and stained with hematoxylin and eosin (HE), while the remainder was stored at -80 °C. Blood samples were incubated at 4 °C for 2 hours, then centrifuged at 3000 rpm for 10 minutes to separate serum, aliquoted into EP tubes, and a portion was immediately used for serum marker testing. The remainder was stored at -80 °C for future testing of other blood biochemical indicators.

[0044] 2. Test Results: Fasting blood glucose levels in mice showed that the HFD group mice had significantly higher blood glucose levels than the CD group mice. Compared with the HFD group mice, the Gua-H and Gua-L group mice had significantly lower fasting blood glucose levels. Figure 5 As shown in Figure A. The GTT results showed that, compared with the CD group mice, the HFD group mice had significantly impaired glucose tolerance, while the Gua-H and Gua-L groups mice had significantly enhanced glucose tolerance compared with the HFD group mice. Figure 5 B and Figure 5 As shown in C. The ITT experiment results showed that compared with the CD group mice, the HFD group mice had significantly reduced insulin sensitivity, while after intervention with guaiacol glycerol ether, the insulin sensitivity of the Gua-H and Gua-L groups mice was significantly improved, as shown in Figure C. Figure 5 D and Figure 5 As shown in E. Therefore, guaiacol glycerol ether has pharmacological effects of improving glucose tolerance and insulin sensitivity in mice, and reducing blood glucose levels in mice.

[0045] Mouse body weight changes were recorded weekly. The HFD group showed a continuous increase in body weight, while the Gua-H and Gua-L groups had significantly lower body weights than the HFD group. Figure 6 As shown in Figure A, the HFD group mice were larger than the CD group mice, while the Gua-H and Gua-L group mice were smaller than the HFD group mice, as shown in Figure A. Figure 6As shown in Figure B. Animal body composition analysis showed that, compared with CD mice, HFD mice had a significantly increased fat mass / body weight ratio (Fat mass / Body weight) and a significantly decreased lean mass / body weight ratio (Lean mass / Body weight). After intervention with guaiacol glycerol ether, both Fat mass / Body weight and Lean mass / Body weight in the mice were significantly improved, as shown in Figure B. Figure 6 C and Figure 6 As shown in Figure D, images of epididymal white adipose tissue (eWAT) and inguinal white adipose tissue (iWAT) in mice show that the eWAT and iWAT volumes in the HFD group were significantly larger than those in the CD group, while the eWAT and iWAT volumes in the Gua-H and Gua-L groups were significantly smaller. Figure 6 As shown in E. Therefore, guaiacol glycerol ether has a pharmacological effect of reducing obesity in mice.

[0046] Comparison of liver images from different groups of mice revealed that the livers of mice in the HFD group were larger and more yellow than those in the CD group; the livers of mice in the Gua-H and Gua-L groups were smaller and paler yellow than those in the HFD group. Figure 7 As shown in Figure A. The statistical results of liver weight analysis in each group of mice showed that, compared with the CD group, the liver weight of mice in the HFD group was significantly increased, while the liver weight and liver weight-to-body weight ratio of mice in the Gua-H and Gua-L groups were significantly decreased. Figure 7 B and Figure 7 As shown in C. Simultaneously, the TG and TC contents in the livers of mice in each group were measured. Compared with the CD group, the TG and TC contents in the livers of mice in the HFD group were significantly increased. After intervention with guaiacol glycerol ether, the TG and TC contents in the livers of mice in the Gua-H and Gua-L groups were significantly decreased, as shown in Figure C. Figure 7 D and Figure 7 As shown in E. Detection of representative liver function indicators revealed that serum ALT levels were significantly increased and the AST / ALT ratio was significantly decreased in the HFD group mice. However, after intervention with guaiacol glycerol ether, ALT levels and the AST / ALT ratio in high-fat diet mice were significantly improved, as shown in Figure E. Figure 7 F, Figure 7 G and Figure 7 As shown in H.

[0047] To clarify the effect of guaiacol glycerol ether on pathological changes in mouse liver, HE staining results showed that the livers of mice in the HFD group exhibited numerous fatty vacuoles. Guaicol glycerol ether administration significantly reduced these fatty vacuoles in the mouse livers. Figure 8 As shown in Figure A. Oil Red O staining results showed that lipid deposition in the liver cells of mice in the HFD group was significantly increased, and intervention with guaiacol glycerol ether reduced lipid deposition in the livers of mice, as shown in Figure A. Figure 8 As shown in B. The above results indicate that guaiacol glycerol ether has the pharmacological effect of alleviating liver damage, reducing hepatic lipid deposition, and improving MASLD.

[0048] Example 3 Guaifenesin alleviates diet-induced choline-methionine deficiency (MCD) in mice with MASH. 1. Materials and Methods: Thirty-two 7-week-old male C57BL / 6J mice were first acclimatized for one week and then randomly divided into four groups: a normal diet control group (CD), a choline-methionine deficient diet group (MCD), a high-dose MCD diet-guaiacol glycerol ether group (Gua-H), and a low-dose MCD diet-guaiacol glycerol ether group (Gua-L). Mice in the CD group were fed a normal diet, while the other groups were fed an MCD diet (XTMCD). Simultaneously, mice in the Gua-H group were administered 300 mg / kg guaiacol glycerol ether daily by gavage, and mice in the Gua-L group were administered 100 mg / kg guaiacol glycerol ether daily by gavage. The guaiacol glycerol ether was dissolved in physiological saline. The other groups were simultaneously administered a blank solution by gavage. This drug intervention continued for three weeks.

[0049] Three weeks after drug intervention, mice were fasted for 12 hours but allowed free access to water. The following morning, after weighing, they were anesthetized with an intraperitoneal injection of avertin, weighed again, and blood was collected from the retro-orbital venous plexus. The mice were then fixed, the abdominal cavity opened, and the liver was quickly freed and removed. The liver was rinsed with 4°C saline, the membrane removed, and the wet weight was measured. Liver indices were calculated. A transverse section of liver tissue was made 1 cm from the edge of the right lobe, fixed with 4% paraformaldehyde, routinely dehydrated, embedded in paraffin, sectioned, and stained with hematoxylin and eosin (HE) and Masson's stain. The remaining liver tissue was stored at -80°C. Blood samples were incubated at 4°C for 2 hours, then centrifuged at 3000 rpm for 10 minutes to separate serum. Serum was aliquoted into EP tubes, and a portion was immediately used for blood index testing. The remainder was stored at -80°C for further blood biochemical analysis.

[0050] 2. Test Results: This study found that the livers of mice in the MCD group were smaller and darker in color than those in the CD group. After intervention with guaiacol glycerol ether, the livers of mice in the Gua-H group were larger than those in the MCD group. Figure 9 As shown in Figure A. Compared to the CD group, the MCD group mice had a lower body weight. After intervention with guaiacol glycerol ether, no significant change in mouse body weight was observed, as shown in Figure A. Figure 9 As shown in B. Compared with the CD group, the liver weight and liver weight-to-body weight ratio of mice in the MCD group were significantly decreased, while the liver weight and liver weight-to-body weight ratio of mice in the Gua-H group were significantly increased, as shown in Figure B. Figure 9 C and Figure 9 As shown in D.

[0051] The analysis of representative liver function indicators revealed that serum ALP, ALT, and AST levels were significantly increased in the MCD group mice, while high-dose intervention with guaiacol glycerol ether significantly reduced ALP, ALT, and AST levels in the mice. Figure 10 A, Figure 10 B and Figure 10 As shown in C.

[0052] To clarify the effect of guaiacol glycerol ether on pathological changes in mouse liver, HE staining results showed that the MCD group of mice exhibited numerous fat vacuoles and altered hepatocyte morphology. Guaicol glycerol ether administration significantly reduced these changes in liver fat vacuoles and hepatocyte morphology in mice. Figure 11 As shown in Figure A. Masson staining results showed that liver fibrosis was significantly increased in the MCD group mice, and intervention with guaiacol glycerol ether reduced the degree of liver fibrosis in the mice, as shown in Figure A. Figure 11 As shown in B. The above results indicate that guaiacol glycerol ether has pharmacological effects in reducing liver damage, decreasing the degree of liver fibrosis, and improving and treating MASH.

[0053] Although the present invention has been described in detail with reference to the accompanying drawings and preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention.

Claims

1. The use of guaiacol or its derivatives in the preparation of drugs for the prevention or treatment of metabolic syndrome, characterized in that, The guaiacol derivatives are guaiacol glycerol ether and guaiacol-glycerol-β-guaiacol propyl ether.

2. The application as described in claim 1, characterized in that, The metabolic syndrome includes metabolic-related fatty liver disease, hyperlipidemia, hypercholesterolemia, obesity, and diabetes.

3. The application as described in claim 2, characterized in that, The metabolic-associated fatty liver disease includes metabolic-associated fatty liver and metabolic-associated steatohepatitis.

4. The application as described in claim 1, characterized in that, Guaiacin or its derivatives are the only active ingredient in the drug.

5. The application as described in claim 1, characterized in that, The guaiacol or its derivatives also include pharmaceutically acceptable salts.

6. The application as described in claim 1, characterized in that, The drugs for the prevention or treatment of metabolic syndrome include pharmaceutically acceptable excipients.

7. The application as described in claim 6, characterized in that, The acceptable excipients are selected from one or more of the following: diluents, disintegrants, precipitation inhibitors, flow aids, binders, dispersants, suspending agents, isotonic agents, thickeners, emulsifiers, preservatives, stabilizers, hydrating agents, ion exchangers, flavoring agents, or antioxidants.

Images